1)Bee's knees
-No one pays attention to women's 200 pound weightlifting at the Olympics, because the Men's 100m sprint is the bees knees.
-Pharrell's new song is the bee's knees.
-Everyone knows the Dark Knight is the bees knees of Superhero films.
Definition: excellent or very high quality.
Etymology: reference to the fact that bees carry pollen in sacks on their knees, and that the expression therefore alludes to this concentrated goodness. Others maintain that the saying is just a corruption of the word 'business'.
2) Cat's pyjamas
-Your drawing is the cat's pyjamas.
-Every party that Jordan organizes is the cat's pyjamas.
-My new Tesla is the cat's pyjamas.
Definition: used to refer to someone or something wonderful or remarkable.
Etymology: American cartoonist Thomas Aloysius "Tad" Dorgan is often credited with coining this colorful phrase,
3) Fat cat
-The fat cat's in the nation's government don't care if middle class workers get laid off.
-Obama's Presidential campaign relied mostly on middle class voters and not on contributions from fat cats.
-Jennifer didn't want her daughter Emma to marry the fat cat Marcus, even if they were poor.
Definition: A wealthy and privileged person
Etymology: This expression dates back to the 1920s in the US whereby it was used to refer to people who made large contributions to political candidates. It is Chinese in origin.